Generally, in an inkjet-type recording device serving as a droplet ejecting device, a droplet ejecting head having nozzles is supported by a carriage. The carriage is moved in a predetermined direction (hereinafter referred to as “main scanning direction”), while ink droplets are ejected from the nozzles of the droplet ejecting head. Each time the movement in the main scanning direction ends, a recording medium (a sheet of paper or the like) serving as an ejection object is moved by a predetermined amount in a sub-scanning direction perpendicular to the main scanning direction, thereby performing a recording operation.
Although ink is held in the nozzles of the droplet ejecting head in preparation for ink ejection, ink is exposed to air at the openings of the nozzles. Hence, if the time period between the previous ejection and the next ejection becomes long, ink at the nozzle openings dries and the viscosity increases gradually. Accordingly, if the next ejection is performed in this state, an ink droplet is ejected in a wrong direction deviated from the normal direction and, in a worse case, nozzles are clogged, which deteriorates the recording performance.
In order to prevent drying of ink at the nozzles, an inkjet recording device disclosed in U.S. Patent Application Publication No. 2006/0187257 A1 (corresponding to Japanese Patent Application Publication No. 2006-231661) moves a carriage supporting an inkjet head to a flushing position outside a recording region periodically or forcibly, prior to the start of a recording operation or during a recording operation. Then, inkjet recording device performs preliminary ejection (flushing ejection) of ejecting ink droplets from all the nozzles toward an ink receiving section.
On the other hand, Japanese Patent Application Publication No. 2006-272754 discloses an inkjet recording device in which an inkjet head is driven to apply small pressure to ink in such a manner that ink is not ejected from nozzles, thereby generating micro-vibration in ink to prevent drying of ink. When small pressure is applied to ink, a meniscus in each nozzle swells and then returns, thereby generating vibration. Thus, ink in the nozzles is stirred and drying of ink can be prevented.